WASHINGTON — Newly released documents show the special prosecutor in the Watergate case expressed “extreme interest“ in a 1970s criminal investigation of Yankees owner George Steinbrenner for illegal campaign contributions.

In an Aug. 16, 1973 memo, FBI Director Clarence M. Kelley also told the Cleveland office of the FBI to ensure that the case “receives the same, immediate and preferred handling“ as others growing out of the Watergate scandal.

Steinbrenner pleaded guilty the following year to two charges in connection with illegal corporate campaign donations to both Nixon and Democratic lawmakers and was fined $15,000.

The memo was included in a 400-page release of Steinbrenner’s FBI file today. Steinbrenner died in July.